1. Field of the Invention
The present invention relates to a system for radiation dosimetry and, more specifically, to a fiber optic dosimeter using electron trapping materials employing a technique for eliminating background fluorescence.
2. Description of the Related Art
Two types of devices are commonly used for radiation dosimetry: continuous radiation monitors or integrating radiation monitors. The most widely used continuous monitors are ionization-type dosimeters, which work by measuring the current produced when radiation ionizes a known volume of a gas, usually air. Integrating dosimeters, on the other hand, measure the total radiation dose received over a fixed period of time. The most common integrating dosimeters are thermoluminescent dosimeters (TLD's). TLD's consist of a type of storage phosphor which, after exposure to ionizing radiation, produces a luminescence when heated, the magnitude of the luminescence being proportional to the radiation exposure.
One problem with existing commercial dosimeters is that they are usually large in size and thus not suitable for use in small or inaccessible areas. Moreover, ionization-type dosimeters require an electrical cable between the probe and the read-out instrument which is susceptible to electromagnetic interference. Also, because the electrical currents produced are usually quite small, the cable must be very short to minimize resistance. Finally, both integrating and continuous radiation monitors are generally limited to a narrow dynamic range of radiation intensities and thus require several different probe configurations to measure over a wide range of radiation intensities.